In the processing of chickens, turkeys, and other types of birds through a poultry processing plant for defeathering, evisceration, cut-up and packaging and for delivery to retail grocery stores, fast food restaurants, etc., it is highly desirable to perform as many of the processing steps as possible with automated machinery. It is important to minimize the amount of manual handling of the birds so as to minimize the expense of processing and to uniformly cut apart the birds.
The general trend in poultry processing in recent years has been to suspend birds by their legs from an overhead conveyor system and perform as many of the processing steps as possible as the birds are being moved in series on the conveyor system from one processing station to the next. For example, the birds can be defeathered, decapitated, opened and eviscerated while being progressively advanced along an overhead conveyor system. Additionally, it is desirable to cut apart the birds and to remove the fat from the visceral cavities of the birds while the birds move on an overhead conveyor system to avoid the manual handling of the birds while the cutting and removal functions are being performed. A cut up system of this type is disclosed in my prior U.S. Pat. 4,574,429. However, it is still common practice to first remove the birds from the overhead conveyor system prior to cutting them apart, with the removal of fat from the carcasses often performed manually.
One of the problems with the prior art poultry cut up machines of the type that cut the birds while the birds are suspended from an overhead conveying system is that it is difficult to accurately position and maintain the birds in alignment with the cutting elements of the cut up machine so that proper cuts are formed in the carcasses. When birds of different sizes enter the machine, the larger or smaller birds tend to approach the cutting elements at positions that are too low or too high for the cutting elements.
Some prior art processing systems have been developed that use mandrels to support the birds during the cutting steps. A cut up system of this type is disclosed in my prior U.S. Pat. No. 4,559,672. The birds are each positioned with their previously eviscerated visceral cavities mounted on a mandrel. This supports the carcass at a predetermined position without regard to the lengths of the legs of the birds, and the mandrels tend to expand the skeletal elements of the birds to shapes corresponding to the mandrel. However, most of the poultry cut up machines that use mandrels require the birds to be mounted by hand on the mandrels.
Additionally, the fat of the visceral cavities of the carcasses typically is removed by hand, by using a knife or scraper tool. The use of such knives or scraper tools is labor intensive and can damage the meat and bones of the poultry carcasses, possibly chipping the bones or tearing the meat of the carcasses. Automated fat removal systems such as described in U.S. Pat. No. 4,776,063 have been developed for the automated removal of fat from poultry carcasses. However, such machines are designed solely for removal of fat from the carcasses and must be positioned in the processing line prior to the carcass cut up equipment, thus requiring additional processing steps in the processing of the carcasses.
Therefore, it can be seen that it would be desirable to provide an improved, reliable and accurate method and apparatus for use in a poultry processing line for simultaneously removing the breast portions from the carcasses of the birds and removing the fat from the visceral cavities of the birds as the birds are moved in series along an overhead conveyor system.